Electric switch



Aug. 13, 1929. w RANKIN 1,724,776

ELECTRIC SWITCH Filed Jan. 31, 1924 2 Sheets-Sheet 2 fi,z CONTROLS Mari? FORPUMPZ o o F g, ile

Z9 5 3/ I I a -o g O .69 f 58 L x Q )1 lnyentor'. 5 WiLLiarnKRanKin. Y bg Hi Attorneg.

Patented Aug. 13, 1929.

UNITED STATES WILLIAM K. RANKIN, 0F SCOTIA, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

Application filed January 31, 1924.

My invention relates to mechanism for the operation of electric switches and particu larly switches of large construction and of the fluid break type. An object of my invention is to provide an improved switch actuating mechanism whcih shall have the force necessary to throw the switch to closed or open position, which is quick to respond to the controlling device to facilitate synci'ironizing and which constructed in a manner to prevent its being operated except in a predetermined manner.

In accordance with my invention I employ springs for providing the necessary force for actuating the switch mechanism in both the closing and opening movements. For stressing the springs preparatory to an OpQl'flElOIl of the switch I employ hydraulic means comprising a piston and cylinder and motor driven pump, the starting of. the motor and the adniission of the operating fluid through a suitable valve to the cylinder being controlled by the closing of a control switch by the operator. By a single traverse of the piston under the pressure of the fluid, three separate springs are compressed namely, a piston return spring, a switch closing spring, and a switch opening spring. Upon reaching the end of its stroke the p ston uncovers a port through which the fluid pressure 1n escaping actuates the main valve to exhaust position, permitting the pistonto return under the action of its return spring. Locking mechanism including trip free toggles is providcd for maintaining the switch closing and switch opening springs compressed after the return of the piston. At the instant the switch is to he closed the operator closes a control circuit which actuates a solenoid to trip the toggle which retains the switch closing spring and when it is desired to open the switch manually a second control switch is closed which actuates a solenoid to trip the toggle which retains the switch opening spring. The latter toggle may also be tripped automatically by a protectrve relay 1n the usual and well known manner.

My invention will be better understood by reference to the accompanying specification and drawings and its scope will be pointed out in the appended claims.

In the drawings, Figure l is a diagrammatic representationot my invention with the parts shown in released, open circuit position,- Figs. 2 and 3 are similar views with serves to return the Serial No. 689,826.

the parts respectively in spring compressed open circuit position and in closed circuitposition; and Fig. 4 is a view showing the operating mechanism connected to a switch to be operated thereby, the switch being closed.

Referring first to Figure 1, the reservoir 1 containing a suitable liquid preferably oil is connected to the motor driven pump 2 by pipe 3 and the pump in turn connects through inlet pipe st with the valve casing 5. The reservoir and the valve casing are also connectct together by the exhaust pipe 6. The valve casing is formed interiorly with a larger upper bore and a smaller lower bore in which slides the valve '7 having piston-lineends to lit the respective bores. The valve is also provided with a small bleed opening extending longitudinally thereof. The cylinder 9 in which slides a piston 10 is shown integral with the valve casing and communicates with the lower bore thereof by means of a port 11. In the upper part of the valve casing is a valve 12 controlled by a solenoid 1.3 for con necting by means of pipe 14 the upper portion of the valve casing 5 with the outer portion of the cylinder Piston 10 is of cup-shape format-ion and is adapted to receive a second piston 16, the two pistons forming with each other an air cushion or dash pot which absorbs the momentum of the heavy moving parts and prevents a hammer blow which might rack the apparatus apart. Piston 10 is attached to a rod 17 having ,on its opposite end a flange for engaging a compression spring 18 which spring is contained in a housing 19 and piston 10 to its original position. Piston 1G is secured to one end of a tube 20, the opposite end of which carries a cross head 21. The housing 22 is secured to and forms an extension of the cylinder 9 while the outer end of the housing forms a bearing for the tube 20. Two compression springs encircle the tube 20, the smaller one 23 abutting the piston 16 and the larger one 24 abutting the ring 25 whose movement in one direction is limited by ongagement with the outer end of the cylinder 9. Slidably mounted on the tube 20 is the cross head 27 carrying spring supporting tubes 28 and between the-cross head 27 and the plates 29 on the ends of rods 30 carried by the cross head 21 are compression springs 31. Cross head 21 is connected by means is adapted to be over set and in this positionretains the cross head againstinovement to the left under the influence of springs 23, 24 and 31. The plunger 40 actuated by the solenoid 41 causes the toggle to buckle and thus to release the cross head 21. Cross head 27 is similarly connected by the link 43 and arm 44 to the shaft 45 and through link 46 and bell crank 47 to the toggle 48. This toggle is also adapted to be over set when the cross head is in the position illustrated by Fig. 1 and in this position retains the cross head against movement to the right under the influence .of springs 31. Plunger 50 actuated by solenoid 51 causes the toggle to buckle and thus to release the cross head 27.

Manual control of the above described mechanism is had through three control switches 52, 53 and 54, each of which has associated therewith a signal light 55 in the well known manner. Switch 52 is connected to solenoid 13 controlling valve 12 for admitting oil to the cylinder 9 for compressing the springs and this switch also has an additional contact by which a circuit is closed at the same time through a relay 56 by which is controlled the circuit of the motor (not shown) for driving the pump 2. Switch 53 is connected to control solenoid 51 and switch 54 is connected to control solenoid 41. For preventing an improper sequence in the operation of the apparatus suitable auxiliary switches are employed. Thus auxiliary switch 57 in the circuit of solenoid 51 is held open by a. spring during the interval that the rod 17 is displaced .from the position illustrated by Fig. 1 and is closed by engagement of a lug on rod 17 with a portion of the switch upon the return movementof the rod. Auxiliary switch 58 is operatively connected to the shaft 34, the connection being indicated by a dotted line and serves to control the circuit of the valve solenoid 13 and the circuit of the tripping solenoid 51. Similarly auxiliary switch 59 is operatively connected to the shaft 45 where the connection is also shown by a dotted line, and serves to control the circuits of tripping solenoids 51 and 41.

In order to prevent a rebound of the crosshead 27 when it strikes the cross-head 21 in moving from the position shown in Fig. 2 to that shown in Fig. 3, arms 35 and 44 are provided respectively with cooperating hooks '60 and 61, the former being rigid while the latter is pivotally mounted and has two lugs 62 and 63 which engage the sides of the arm 44 and limit the extent of the relative movement. When the arms 35 and 44 are in the position shown by Fig. 3 the hooks engage'one another and prevent any rebound of the cross-head 27 and parts associated therewith. As the arms move in a counter-clockwise direction the hooks automatically disconnect from each other.

In the diagram comprising Fig. 4 l have shown the switch operating mechanism mounted on a floor 65 and having its arm 44 operatively connected to a single oil switch 66 located on the floor below. Parallel motion mechanism for the switch is shown at 67 located in the same floor as the operating mechanism and connected thereto by the rod 68 and to the switch by the rod 69. While I have shown but one switch 66 and parallel mechanism connected to the operating mechanism, it will be obvious that a plurality of switches and parallel mechanisms may be connected to the arm 44 in which case the switches may if desired be located on opposite sides of the operating mechanism or may be located all on the same side of the operating mechanism with the connecting rods arranged in tandem. The arrangement moreover need not necessarily be horizontal, as illustrated, but may be vertical. with the switches arranged one above the other and on separate floors if desired.

The operation of the above described mech anism is as follows: Assuming the parts to be in the position illustrated by Fig. 1 in which position the main switch is open. To close the main switch the operator first closes the control switch 52 whereby the auxiliary switch 56 is energized to start the motor driven pump 2 and whereby the valve 12 is opened permitting the escape of oil from the upper portion of the valve casing 5. Valve 7 thereupon moves upwardly uncovering the port leading into the cylinder 9 whence the piston 10 is pushed to the right compressing the springs 23, 24, 31 and 18. This position of the parts is illustrated by Fig. 2. Upon reaching the end of the stroke the cross head 21 becomes locked by its toggle 38 and at the same time the piston 10 uncovers the end of pipe 14 whereupon oil flows back through valve 12 into the upper chamber of valve casing 5. Valve 7 returns to its original position connecting the cylinder 9 with the exhaust pipe 6 permitting spring 18 to return the rod 17 and piston 10 to their original positions. In this manner energy for the subsequent operation of the main switch is stored in the springs 23, 24 and 31 but it will be noted thatuntil the piston 10 shall have completely returned and the switch 57 been closed a closing of control switch 53 is ineffective to trip toggle 48. Also by reason of auxiliary switch 59, a closing of control switch 54 is ineffective to trip toggle 38. At the instant at which it is desired to close the main switch the operator closes the control switch 53, the auxiliary switch 57 in the meantime having been closed by the automatic return of the piston 10 and the rod 17. Toggle A8 is caused to buckle and the cross head 27 is pushed to the right by spring 31 exerting a pull on red 68 to close the main switch. Both auxiliary switches 57 and 58 are now (see Fig. 3) in such a position that the closing of either cont-rel switch 52 or 53 would be ineffective. If the main switch is to be opened manually control switch 5-1 closed whence toggle 38 is caused to buckle and the force of the springs 23 and 24 is spent in moving both cross heads 21 and 27 to the left and in shifting the switch operating rod 68 to the left. lVhen the switch and operating mechanism are of large proportions, springs 23 and 24 must be of relatively great power in order to provide suilicient reserve power to insure a complete closure of the switch under all circumstances. As the piston 16 reaches the inner end of its stroke the moving parts connected therewith have acquired consider able momentum which is only partly abysorbed by the switch the remainder being absorbedby the air cushion between oistons 10 and 16, thus relieving the mechanism of an otherwise severe hammer blow. The apparatus is thus returned to its original position illustrated by Fig. l where the auxiliary switches 58 and 59 are in such a position that the closing of control switch 52 only, can have any effect upon the apparatus.

lVhile I have described only one embodiment of my invention, I do not wish to be limited to the particular form shown and described as it will be apparent that many modifications therein may be made without departing from the scope of my invention as set forth in the appended claims.

WVhat I claim as new and desire to secure by Letters Patent of the United States, is

1. A switch operating mechanism comprising a plurality of resilien switch actuating members, means for storing energy simultaneously in each of said resilient members, separate means whereby one of said resilient members upon being released closes said switch and means whereby another of said resilient members upon being released opens said switch, said two latter means being independent of the operation of the first mentioned means.

2. A switch operating mechanism comprising a. resilient switch closing member, a resilient switch opening member, common means for putting both said members under stress simultaneously, and means independent of said common means whereby said closing member and opening member may be respectively released, whereby said switch may be closed and opened.

3. A switch operating mechanism comprising a plurality of springs, means for simultaneously stressing said springs, means for another part of the energy stored to open said switch, and a plurality of control devices operated independently of said energy storing means and characterized by the fact that the operation of one of said control devices 0 causes energy to be stored in said first means, the operation of another of said control devices causes energy to be released. from said first means to close said switch and the operation of another of said control devices causes energy to be released from said first means to open said switch.

5. A switch operating mechanism com prising a plurality of springs, a stationary support for one end of one of said springs. a movable support for one end of another of said springs, means engaging the opposite end of each of said springs for stressing the same, a switch operating member operatively connected with said movable latching means for controlling the forward spring actuated movement of said movable support and for controlling the return spring actuated movement of said stressing means.

6. A switch operating mechanism comprising a switch closing spring, a switch opening spring, fluid pressure actuated means for compressing said springs, electromagnetic means for controlling said fluid pressure means, a cross head operatively connected with said switch and comprising a movable abutment for said closing spring, a toggle mechanism for retaining said cross head and switch in circuit closed position, a toggle mechanism for retaining said spring compressing means in its actuated position, electromagnetic means for releasing each of said toggle mechanisms and a switch for controlling each of said electromagnetic means.

7 A switch operating mechanism comprising resilient actuating means, hydraulic means for storing energy in said actuating means and latching means for controlling the release of said actuating means, said hydraulie means comprising a cylinder, a piston therein and a second piston operatively connected with actuating means and cooperating with said first piston to constitute a dash pot.

S. A switch operating mechanism comprising a compression spring, actuating means operatively connecting said spring and said switch, hydraulic means for compressing said spring and latching means for controlling the release of said spring, said hydraulic support and ill) means comprising a cylinder, a piston therein, and a second piston engaging said spring and fitting into said first piston to form a dash pot therewith to cushion the final movement of said actuating means when said spring is released.

9. In a. switch operating mechanism having a spring adapted to close the switch, means including a toggle for retaining said spring stressed, means actuated by said spring to close said switch and to be moved into engagement with said first means, and latching means for preventing a rebound of said second means upon its engagement with said first means.

10. Switch operating mechanism comprising energy storing means, a member operable by a single operation thereof, to store energy in said means, means for retaining said means in the condition of stress when said member is returned to its original position, a switch operating member adapted to move in opposite directions, and means constructed to use a part of the energy stored in said first means for moving said member in one direction and to use another part of the energy stored therein for moving said member in the opposite direction.

11. Switch operating mechanism comprising energy storing means, motor operated means for storing energy in said means by a single operation thereof, means for returnmg said motor operated means to its original position, a switch operating member arranged to move in opposite directions respectively to close and open a switch, means operable by the release of part of the'stored energy in said first means to move said member in one direction and operable by the release of another part of the stored energy to move said member in the opposite direction, and electromagnetically operated latching means for controlling the movements of said switch operating member.

12. Switch operating mechanism comprising a plurality of resilient members, means for stressing said members for storing energy simultaneously therein, toggles for retaining each of said members under stress, means separate from and independent of said stressing means for releasing the respective toggles, and a switch actuating member arranged to be moved by said resilient members respectively to close and open a switch.

13. Switch operating mechanism comprising a plurality of springs, means for simultaneously stressing said springs, means for separately retaining said springs under stress, an actuated member arranged to be moved in opposite directions by the respective springs, and means for releasing the retainmg means.

In witness whereof, I have hereunto set my hand this th day of January 1924:.

VILLIAM K. RANKIN. 

